Ah crap, now you all are gonna think I am a tweaker, too. Oh well, here goes- I use Auric Illuminator and I can hear a differance, after treating the disc. I am less shure about the edge treatment having an effect (Auric's edge pen is black), but I can tell you the cleaner/polish fluid does work. It also makes a difference in the clarity of the surface of the plastic, and works really good to clean the plastic lenses in my eye glasses. (Very clear and colors seem brighter too, when I do my glasses. )
I will suggest that you could probably get the same effect with other plastic polish, de-static-ing fluids, though.
Now the really weird admission. I have NEVER been a beliver in the de-magnatiser devices that some people use on CD's, but, at the VSAC show in one room, the guy popped out the disc we were listening to, took it over to his homemade de magnatizer, gave it a couple of cranks, and stuck it back in the player, and pressed play. I looked at the guy next to me and he said what I was allready thinking- "Crap, I really didn't expect to hear any difference, and I do." I will readily admit that I had to have been a victim of the placibo effect, because I still can't believe it made a difference. Weird.